Submitted to: Swine Improvement Federation Proceedings
Publication Type: Other
Publication Acceptance Date: 12/4/2014
Publication Date: 12/5/2014
Citation: Lents, C.A. 2014. Research in gilt development to improve lifetime productivity of sows [powerpoint]. Swine Improvement Federation Proceedings, 4-5 Dec 2014, Lincoln, NE. Available: http://www.nsif.com/Conferences/2014/contents.html/.
Technical Abstract: Proper development and selection of gilts is essential to the productivity and longevity of the sow herd. A gilt must remain in the sow herd for 2 to 3 parities before she produces enough piglets to pay for the cost of her development. Average age at culling in U.S. swine herds is approximately 3.5 parities, which means many replacement gilts fail to stay in the herd long enough to become profitable. Well developed gilts are defined as having high growth rates, reaching puberty early, having high fertility, good lactation performance, and the ability to stay in the herd for multiple parities. The problem is that at the time a gilt is selected to enter the breeding herd, it is unknown whether she will have this future phenotype. In order to improve the efficiency of swine production and minimize the number of gilts that are culled from the herd, genomic and physiological indices that define a gilts potential productivity and longevity need to be discovered. A growing body of evidence suggests that development of reproductive tissues in the pig can be programmed early in postnatal development. Improved development of ovarian and uterine tissue can have long-term impact on increasing productivity of gilts. Genomic markers that explain a significant portion of the phenotypic variation in age at puberty and number of parities in a lifetime have been developed. Many of these markers are located near genes that are involved in regulation of reproductive function by the brain. The biological effects of these genetic markers can differ with level of growth during development. Recent evidence indicates that limiting growth of gilts during development may lead to sows that produce more pigs and stay in the herd longer.